Unit 2 Healthy eating Section Ⅳ Grammar & Writing 情态动词(Ⅱ) [语法感知] 观察并研究下面的句子，注意句中的黑体部分，完成句后的内容 ①But now his restaurant ought to be full of people. ②Does your father need any help? ③What do we need to take for the picnic? ④There is enough time.You needn't hurry. ⑤His mother is ill.He has to stay at home to look after her. ⑥Something terrible must have happened if Li Chang was not coming to eat in his restaurant as he always did. (1)以上句子中，第________句中的黑体词都是情态动词，而第________两句中的黑体词是实义动词。 (2)以上各句中的情态动词后都接动词原形。其中第⑥句中must have happened 的意思是“________”。 (3) 上 述 句 子 中 ought to 意 为 “________” ； need 意 为“________”；has to 意为“________”。 答案：(1)①、④、⑤、⑥；②、③ (2)一定已经发生了 (3)应该；需要；不得不 [语法点津] 一、ought to 的用法 1．表示责任和义务，意为“应该”，与 should 同义，只是语气重一些。如要反映客观情况或涉及法律义务和规定时一般用ought to。 I feel that we ought to accept his proposal. 我觉得我们应该接受他的建议。 You are his father.You ought to get him to receive good education. 你是他的父亲。你应该使他接受良好的教育。 [注意]ought to 的否定形式为 ought not to(oughtn't to)；一般疑问形式是将 ought 置于主语前，其否定答语通常用 don't have to或 needn't。在反义疑问句中，常省掉 to 用 oughtn't 或 shouldn't。而在美式英语中常用 shouldn't 代替 oughtn't to。 You ought not to do it. 你不应该做这事。 —Ought he to start now? ——他现在该动身了吗？ —Yes，he ought(to)． ——是的，该动身了。 —No，he doesn't have to/needn't. ——不，他不必。 They ought to go now，oughtn't they? 他们现在该走了，对吗？ 2．表示可能性，一般指较大的可能性，意为“按道理应该”。 They ought to win—they've trained hard enough. 他们应该能赢，他们训练得够刻苦的了。 If he started at six，h...
